Here's a letter to the head of the World Wildlife Fund that explains the precise nature of WWF's Earth Hour:
Dear Mr. Roberts:
You and members of your organization worry that industrialization and economic growth are harming the earth's environment. I worry that the intensifying hysteria about the state of the environment - and that the resulting hostility to economic growth - might harm humankind's prospects for comfortable, healthy, enjoyable, and long lives.
So I commend you on your "Earth Hour" effort. Persuading people across the globe to turn off lights for one hour supplies the perfect symbol for modern environmentalism: a collective effort to return humankind to the dark ages.
Donald J. Boudreaux
[Hat tip Anti Dismal]